The ⁷Li(α, γ)¹¹B Reaction

The reaction ⁷Li(α, γ)¹¹B has been studied at the three resonances found at 951, 815 and 401 keV. The decay schemes have been established, and it is shown that at the two upper resonances the decay via the 6.76-6.81 MeV doublet involves only the 6.76 MeV member. The analysis of the experimental data on angular correlations establishes the resonance spins, and also shows the 6.76 MeV and 4.46 MeV levels to have spins 7/2^- and 5/2^- respectively. The transition from the 4.46 MeV state to ground is found to have an E2/M1 mixing amplitude of +0.20±0.02.

The properties of the 6.76 MeV level are not as predicted by the independent particle model.